Catenary supporting cable construction



1957 L. P. FRIEDER ET AL CATENARY SUPPORTING CABLE CONSTRUCTION FiledFeb. 12, 1953 IN V EN TOR. 150M490 P. FP/EOEP Y W41. TEE S. HA/KEA/ L A7'7'0PA/E) construction for use in portable shelters.

United States Patent CATENARY SUPPORTING CABLE CONSTRUCTION Leonard P.Frieder, Great Neck, and Walter S. Finken, Brooklyn, N. Y.; said Finkenassignor to said Frieder Application February 12, 1953, Serial No.336,482

'7 Claims. (Cl. 189*34) Our invention relates to an improvement incatenary supporting cable construction.

Catenary cables have long been used to support large loads over alongspan without the use of intermediate sup- .porting members. In ourcopending application, Serial No. 297,006, filed July 3, 1952, nowPatent No. 2,693,195, we have disclosed broadly a catenary supportingcable In this construction centenary cables supporting crescent trussesto which loads are applied are supported between a pair of poles. Toreduce the bending moments on these poles and the tension on the guywires supporting the poles, we provided compression members surroundingthe cable which absorb part of the load applied to the guy wires. Insuch a construction it is desirable that the cable assume a position asclose as possible to catenary form and where compression members areused, means should be provided to prevent seizure of the cable betweencompression members. We have invented an improved structure whichensures that the cable will assume a position close to catenary form andwhicheliminates the possibility of seizure of the cable betweencompression members as well as providing an improved means for attachingthe cables to the end poles.

One object of our invention is to provide an improved catenarysupporting cable construction wherein compression members are used'whichare joined by knuckle joints without the use of bolts.

Another object of our invention is to provide a catenarysupporting'cable construction using compression members joined byknuckle joints wherein the male members of the joints have tapered holesto ensure that the cable assumes a position as close as possible tocatenary form.

A further object of our invention is the provision of an improvedcatenary suporting cable construction in which thimble members forreceiving a load are rotatably supported with respect to the cableitself.

Other and further objects of our invention will appear from thefollowing description.

In the accompanying drawings which form part of the instantspecification and which are to be read in conjunction therewith and inwhich like reference numerals are used to indicate like parts in thevarious views:

Figure l is a perspective view of our improved catenary supporting cableconstruction.

Fi ure 2 is an enlarged view partly in section of our improved catenarysupporting cable construction.

Figure 3 is a sectional view taken along the line 33 of Figure 2.

in general our invention contemplates the provision of an improvedcatenary supporting cable construction in which compression memberssurround the cable to absorb part of the load applied to the guy wires.A number of knuckle joints connect these compression members and themale members of the joints are provided with tapercd holes so that thecable will assume a position as close as possible to catenary form. Wealso provide thirnble members rotatably mounted with respect to thecable for receiving the load and transmitting it to the cable andspecific means for attaching the cable to the end poles.

More particularly, referring now to the drawings, a catenary supportingcable 10 is supported between a pair of tubular end poles 12 havingcrowns .13 and which are held in an upright position by means of guys 14attached to the end poles in any appropriate manner as by brackets 16having eyes 18 and attachedto stakes '20 fixed in the earth. Guys 14 areattached to eyes 18 by appropriate means such as eye splices .19. Theends of the cable 10 are spliced at a point indicated by referencecharacter 22 to form loops passing through the eyes 48 of eyebolts 50having shanks 52. We form each of the shanks 52 with a noncircularcross-sectional shape up to the point where the thread begins. Shanks 52extend through openings 54in the walls of end poles 12 and through holes56 in contour pads 58 inside poles 12. Contour pads 58 are shaped toregister with the interior surface of the corresponding pole 12 andholes 56 have noncircul'ar cross-sectional shapes corresponding to thoseof shanks 52. We thread nuts 60 on the ends of shanks '52 and providesecond openings 62in poles 12 for access to nuts 60.

When a load is applied to the cable, bending moments on the end poleswill tend to pull the tops of the poles toward each other, and thistendency is resisted by guys 14. Where the loads are extremely large andthe span of great length, .it is extremely diflicult to drive stakes 20into the ground securely enough to enable guys 14 to overcome thismovement. In order to minimize this diificulty and to absorb some of theload applied to the guys, we provide a plurality of tubular compressionmembers 26 surrounding the cable 10 throughout its length. When tensionon the cable tends to pull the tops of the end poles together, thecompression members 26 resist the pull, thus "reducing the tension onthe guys 14 and the pull on stakes 20.

Between each pair of'compression members 26 at the points at which theload is to be applied, we provide thimble or shoe members 28 adapted totransmit the load to be supported to the catenary cable. We mount thethimbles on a pair of'bus'hings 30 arranged on a sleeve 32 surroundingthe cable. Since we mount members 28 on bushings, they can rotate withrespect to the cable to accomm'odateshifts in direction 'of the forceapplied by the load.

To -join the compression members with the thimble member '28 in such amanner 'as to' ensure an efiicient transmission of the compressiveforces, we provide a plurality of knuckle joints indicated generally at34. These knuckle joints 34 are made up of male members 36 which may befixed in the ends of compression members 26 by suitable means such asscrews 38 and female members 40 secured to sleeves 32 in any desiredmanner as by welding, for example. For joining the compression membersto the end poles, we provide similar knuckle joints 34.

Along the length of cable 10, within the compression members 26, Wedispose spacers or positioning members 44 to maintain the centrallocation of the cable with respect to the compression members and toprevent members 26 from buckling under compression. It will be notedthat we form the male members 36 of the knuckle joints with taperedholes indicated by reference numeral 46. These tapered holes preventseizure of the cable when the joints are flexed and permit the cable toassume a position conforming more nearly with catenary form.

It is to be emphasized that any number of compression members 26 may beused, depending upon the length of the span. In addition, we may employa plurality of thimble members to support a plurality of loads and jointhe thimble members to the compression members in the manner shown.

In use, a load is applied to the cable through a member inserted inthimble 28 which is rotatably mounted with respect to the cable so as tobe positioned in conformity with the direction from which the load isapplied. When the load is applied, the cable will be under tension andtend to draw the tops of end poles 12 together. Compression members 26will resist this tendency. That is, in operation they reduce the bendingmoments on the end poles and thus the tension onguys 14 and the pull onstakes 20. Our knuckle joints 34 insure that the compressive forceswillbe transmitted efliciently through the compression members along thelength of the cable regardless of the degree to which the cable isflexed. The tapered holes in the male members of the joints permit thecable to assume a more natural position at the points at which it isdeflected and thus prevent seizure.

It will be appreciated that the cable 10 will stretch when undertension. This stretch is compensated for by turning nuts 60 to draweyebolts 50 into the end poles to take up the slack. Bolts 50 areprevented from turning during this operation by the noncircularcross-sectional shape of their shanks, the corresponding cross-sectionalshape of holes 56 and the shape of contour pads 58.

It will be seen that we have accomplished the objects of our invention.We have provided a caternary supporting cable construction usingcompression members in which the compressive forces are efficientlydistributed, notwithstanding the degree to which the cable is flexed. Wehave provided a rotatably supported thimble member -for receiving loadswhich will accommodate shifts in the direction of the load. In addition,we have provided a specific means for securing the cable to the poleswhereby slack due to cable stretch can be taken up and an over-allstructure which enables the cable to assume a position as close aspossible to caternary form.

It will be understood that certain features and subcombinations are ofutility and may be employed without reference to other features andsubcombinations. This is contemplated by and is within the scope of ourclaims. It is further obvious that various changes may be made indetails within the scope of our claims Without departing from the spiritof our invention. It is therefore to be understood that our invention isnot to be limited to the specific details shown and described.

Having thus described our invention, what we claim is:

l. A caternary supporting cable construction comprising in combination acable, a pair of members between which said cable is suspended, aplurality of compression members freely carried by said cable anddisposed along the length thereof, and pivotal means providingconnections between said compression members, said pivotal connectingmeans being" constructed to permit relative movement along the length ofsaid cable between a pair of connected compression members.

I 2. A catenary supporting cable construction as in claim 1 wherein saidpivotal means are knuckle joints, said joints including male membershaving tapered holes therein through which said cable passes and femalemembers having recesses for the reception of said male members.

3. A catenary supporting cable construction as in claim 1 wherein saidcompression members are tubular and fitted with positioning means havingholes through which the cable is passed, said positioning meansmaintaining the cable substantially coaxial with said compressionmembers and preventing the compression members from collapsing undercompression.

4. A catenary supporting cable construction as in claim 1 includingadjustable means for attaching said cable to each of said pair ofmembers.

5. A catenary supporting cable construction comprising in combination acable, a pair of end members between which said cable is suspended, aplurality of compression members disposed along the length of saidcable, a load-receiving thimble member positioned between a pair of saidcompression members, means for rotatably supporting said thimble memberwith respect to the cable, and pivotal means connecting the compressionmembers adjacent the ends of said cable to said pair of end members, andpivotal means connecting said thimble member to adjacent compressionmembers.

6. A catenary supporting cable construction as in claim 5 includingpivotal means connecting contiguous compression members with oneanother.

7. A catenary supporting cable construction as in claim 5 wherein saidmeans for supporting the thimblc members includes a sleeve surroundingthe cable and bearing means carried by said sleeve.

References Cited in the file of this patent UNITED STATES PATENTS989,539 Seeberger Apr. 11, 1911 2,622,546 Kramrisch Dec. 23, 19522,693,195 Frieder et al Nov. 2, 1954 2,704,522 Frieder et al. Mar. 22,1955 FOREIGN PATENTS 3,909 Great Britain Oct. 23, 1877

